fix missing dereferencing in must_strcat_pid
fix missing dereferencing in must_strcat_pid

Fixes a segfault when reading a /tasks file of a cgroup
containing a large number of pids.

Signed-off-by: Wolfgang Bumiller <bac7898f539fd233d9ce33be7a9eda13ee647930@proxmox.com>
Signed-off-by: Serge Hallyn <3df611b026e4639bee8aef7a4beb2e39fcebb313@ubuntu.com>

Xeno22/lxcfs,evgeni/pkg-lxcfs-debian,Xeno22/lxcfs,evgeni/pkg-lxcfs-debian